The effects of low to intoxicating levels of alcohol and of related substances on the structure and function of nerve and cell membranes are to be investigated. Transmembrane potentials and membrane impedance of nerve are measured with microelectrodes. Relative permeabilities of the nerve membrane to sodium, potassium, and cloride ions are determined by recording both the membrane resistance and potential changes resulting from ionic changes in the external media. The regulatory sites for ionic permeation are identified by biochemical alteration of the components in the nerve surface membrane. Alcohol and other substances are added to the bathing medium before and after the use of chemical agents. The effects on ion permeability and membrane resistance are measured and the affected regulatory sites identified. Dependency to alcohol will be produced, and the effects of dependency and withdrawal on membrane function determined. Further information on the mechanism of action for alcohol and similar membrane acting aubstances will thus be determined.